What is a bajo de unas instrument?

A bajo de unas is a type of double bass that is traditionally used in Latin American music, particularly in genres such as salsa, merengue, and cumbia. It is similar to the acoustic bass guitar in terms of size and construction, but it is typically played in a more upright position and has a deeper, more resonant sound. The bajo de unas is typically made of wood and has four strings, tuned to the notes E, A, D, and G. It is played using the arco (bow) and the pizzicato (plucking) techniques.